Learn Farsi: گسل بر این تنگه تاثیر گذاشت.

The compound verb ta'sir gozâshtan literally means to put an effect. When you want to say you influenced or had an effect on something, you use the preposition bar (or sometimes ru-ye) before the object receiving the effect. Here, the fault line put an effect on the gorge (bar in tangeh).

How does ta'sir gozâsht relate to the expressions of consequence we are learning, like dar asar-e?

While dar asar-e is a prepositional phrase meaning as a result of, ta'sir gozâshtan is the active verb showing the influence happening. It is helpful to know that asar (result or trace) and ta'sir (effect or influence) come from the exact same Arabic root, so you are looking at two different grammatical forms of the same core concept of cause and effect.

Does tangeh always refer to a gorge on land?

No, tangeh refers to any narrow geographical passage. On land, it translates to a gorge, canyon, or narrow pass, which makes sense here with the geological context of a fault line (gosal). When referring to bodies of water, it means a strait, such as the famous Strait of Hormuz (tangeh-ye hormoz).

Why is bar in tangeh placed before the verb rather than after it like in English?

In standard Farsi, the verb complex usually goes at the very end of the sentence. The prepositional phrase bar in tangeh naturally falls between the subject () and the compound verb (). In casual spoken Farsi, you might hear the prepositional phrase tacked onto the end as an afterthought, but the order shown here is the most structurally sound.